Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:4.1.1.32 (
phosphoenolpyruvate carboxykinase
)
4,204
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In the genome of the marine diatom-Thalassiosira pseudonana, there are several putative genes encoding enzymes potentially constitute a classical C4 type biochemical CO2-concentrating mechanism. Two genes encode a carboxylation enzyme
phosphoenolpyruvate carboxylase
(
PEPC
)1 and PEPC2; and another two encode decarboxylation enzymes, NAD(+)-dependent malic enzyme (NAD-ME) and
phosphoenolpyruvate carboxykinase
(
PEPCK
). These genes were tagged by the enhanced-green fluorescence protein, egfp, ligated in the transformation vector, and transformed into the cells of T. pseudonana for localization of GFP fusion products. The PEPC1:GFP fusion was localized at the matrix of the periplastidal compartment, while the PEPC2:GFP fusion was localized at the mitochondria. The NAD-ME:GFP fusion was localized in the cytosol and the
PEPCK
:GFP fusion at the mitochondria. The transcripts level of NAD-ME was extremely low, and
PEPCK
transcript was significantly induced under the dark, suggesting that
PEPCK
is involved in the dark metabolism such as respiration and amino acid metabolism in the mitochondria. Treatments of low-CO2grown T. pseudonana cells with inhibitors for
PEPCK
and
PEPC
efficiently dissipated the maximum rate of photosynthesis while these treatments did not affect high-affinity photosynthesis. These data strongly suggest that classical C4 enzymes play little role in the
CCM
in T. pseudonana.
...
PMID:Localization of enzymes relating to C4 organic acid metabolisms in the marine diatom, Thalassiosira pseudonana. 2441 92